In the last few decades, a significant increase in the number of vehicles has been witnessed. The exhaust gases released by the vehicles are harmful in nature and contribute to the already alarming atmospheric pollution. With the advancement of automobile technology, various after-treatment systems are being introduced in the vehicles for treatment of the exhaust gases before leaving the vehicles. Usually, for the treatment and reduction of the exhaust gases, reductants, such as anhydrous ammonia, aqueous ammonia or urea are introduced into a stream of exhaust gases by using injectors.
Such injectors are usually designed for working within a predefined operating range of temperature. However during operation, the injector may need to be in contact with the exhaust gases for prolonged periods while injecting the reductants. Therefore, the injector may be exposed to high temperature of the exhaust gases, and thus the temperature of the injectors may vary with time. Such variation in temperature may affect the operation of the injector. In case, the injector gets heated to a temperature beyond the predefined operating temperature range, the injector may fail and have to be replaced. Further, overheating of residual fluid within the injector can cause detrimental corrosion or boiling of the residual fluid, which in turn may damage the injector.
Owing to such frequent failure of injectors, the after-treatment system may demand frequent maintenance and consequently, the downtime would be significantly high. Moreover, considering the cost associated with replacement of the injectors, an operational cost of the after-treatment system would increase significantly. Conventional cooling techniques for the injector employ a flow of coolant fluid through an injector mount which can transfer heat away from the injector. However, such arrangement adds to the complexity of the structure and leads to more points of failure. Moreover, some system operating modes may require the injector valve to close for significant time durations, thereby stopping the flow of the fluid through the injector. Accordingly, cooling the injector with the fluid may not be sufficient across all the operating modes for an exhaust after-treatment system.
WIPO Application Number WO2008/040363 A2 (the '363 application) relates to a nozzle for formation and administrating of droplets of a first fluid into a stream of a second fluid. The '363 application relates in particular to a device and a method for controlling the temperature of a nozzle. The '363 application discloses that the nozzle utilized a cooling sleeve which may include one or more Peltier elements for cooling and/or heating the nozzle. However, the '363 application does not talk about any cooling system disposed in an injector mounting assembly itself. The system disclosed in the '363 application may be complicated to implement, and demand a change in construction of the injectors and the after-treatment system for accommodating the system.